Aramid nanofiber wave-absorbing honeycomb material and preparation method thereof

Abstract

The present invention discloses an aramid nanofiber absorbing honeycomb material and a preparation method, which belongs to the field of absorbing materials. The aramid nanofiber absorbing honeycomb material is prepared by uniformly mixing an absorbing agent with a nanoscale structure and aramid nanofibers with excellent mechanical properties. Compared with the traditional absorbing honeycomb material, the present invention only needs one step to form, which greatly improves the problems of complex process and the like in the current traditional honeycomb preparation process, and is simple to operate, saving time and labor. In addition, the absorbing agent and the aramid nanofiber in the present invention are combined with hydrogen bonds internally, which avoids the disadvantages of the absorbing coating coated on the surface of the traditional absorbing honeycomb material, such as increased weight and easy peeling. The material has excellent mechanical properties and good absorbing properties, and can be widely used in stealth aircraft, stealth ships, communication base stations, electrical equipment and other fields.

Description

Technical Field

[0001] The present application relates to the field of wave-absorbing materials, and in particular to an aramid nanofiber wave-absorbing honeycomb material and a preparation method thereof. Background Art

[0002] With the development of science and technology, the electromagnetic radiation situation has gradually become more complicated, and absorbing materials have become an indispensable part of the military and civilian fields. As a multifunctional absorbing material with good mechanical properties and absorption properties, absorbing honeycomb materials are an important research direction of structural absorbing materials. Traditional absorbing honeycomb materials usually coat a layer of absorbing coating on the surface of the honeycomb, but the absorbing coating has the disadvantages of increased weight, low bonding strength with the shell, and easy peeling due to the organic resin contained in it. Therefore, it is increasingly restricted in practical applications, especially in the aerospace field. In addition, the preparation of traditional honeycombs requires raw material preparation, gluing, hot pressing, trimming, stretching, shaping, dipping, drying, curing and slicing, and the process is relatively complicated.

[0003] The Chinese invention patent with application number 202210881543.3 discloses a wave-absorbing honeycomb material and its preparation method. The wave-absorbing honeycomb is subjected to prepreg, precuring, surface laying of a wave-transparent fiber layer, and RTM curing and molding treatment to obtain a wave-absorbing honeycomb material, which solves the technical problem of unqualified surface quality of parts formed by existing molding technology. However, its process is relatively complicated, with high requirements on equipment, and the wave-transparent fiber layer laid on the surface is easy to peel off.

[0004] Para-aramid nanofibers (ANFs), as a nanoscale fiber, not only have a large aspect ratio and specific surface area, but also retain the excellent properties of macroscopic aramid fibers such as high strength, high modulus, high temperature resistance, acid and alkali resistance, and light weight. However, there are currently no public reports on the preparation of absorbing honeycomb materials using para-aramid nanofibers.

[0005] Therefore, it is currently necessary to solve the problem that the surface coating of the absorbing honeycomb material is easy to peel off. Summary of the invention

[0006] The purpose of the present invention is to solve the problem that the surface coating of the absorbing honeycomb material is easy to peel off. An aramid nanofiber absorbing honeycomb material and a preparation method are provided. The absorbing honeycomb material prepared by para-aramid nanofiber has good mechanical properties and chemical stability, and meets the application requirements in the fields of aerospace and the like.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] An aramid nanofiber wave-absorbing honeycomb material comprises, by weight, 40 to 90 parts of para-aramid nanofibers and 60 to 10 parts of wave-absorbing agents.

[0009] Furthermore, the cell side length of the aramid nanofiber absorbing honeycomb material is 1.5 to 8 mm, the height of the aramid nanofiber absorbing honeycomb material is 0.5 to 3 cm, and the density of the aramid nanofiber absorbing honeycomb material is 50 to 800 kg / m 3 .

[0010] Furthermore, the absorber is a mixture of one or more of carbon nanotubes, MXene, graphene, metal and metal oxide powders and conductive carbon black.

[0011] A method for preparing an aramid nanofiber absorbing honeycomb material comprises the following steps: preparing a para-aramid nanofiber aqueous dispersion by using a DMSO / KOH / H2O mixed system; mixing an absorber with deionized water to obtain an absorber aqueous dispersion; homogenizing the para-aramid nanofiber aqueous dispersion and the absorber aqueous dispersion to obtain an ANFs@absorber mixed solution; performing controllable vacuum-assisted filtration on the ANFs@absorber mixed solution to obtain an ANFs@absorber hydrogel; inserting a mold into the ANFs@absorber hydrogel at intervals, drying, and removing the mold to obtain the aramid nanofiber absorbing honeycomb material.

[0012] Furthermore, the concentration of the para-aramid nanofiber aqueous dispersion is 1 to 5 mg / mL; the concentration of the absorber aqueous dispersion is 1 to 5 mg / mL.

[0013] Furthermore, the solid content of the ANFs@ absorber hydrogel is 1.5% to 2%.

[0014] Furthermore, the homogenization is performed according to a mass ratio of the para-aramid nanofiber aqueous dispersion to the absorber aqueous dispersion of (40-90): (60-10); the homogenization pressure is 500-2000 bar, and the number of homogenization times is 15-30 times.

[0015] Furthermore, the absorbent is mixed with deionized water by stirring ultrasound, the stirring speed is 900-1500 rpm, the power of the ultrasound is 600-1200 W, and the time of the ultrasound is 10-30 min.

[0016] Furthermore, the mold is a regular hexagon, the side length of the mold is 1.5 to 8 mm, the height of the mold is 1.5 to 4 cm, and the distance between the molds is 0.5 to 3 cm.

[0017] Furthermore, the drying temperature is 30 to 105° C., and the drying time is 12 to 48 hours.

[0018] Compared with the prior art, the present invention has the following beneficial technical effects:

[0019] The present invention uses only aramid nanofibers and absorbers as raw materials for preparing absorbing honeycomb materials. Compared with the traditional method using organic resin adhesives with poor heat resistance, the present invention not only improves the thermal stability of the absorbing honeycomb materials, but also avoids the problems of weak adhesive bonding and easy peeling.

[0020] The present invention provides an aramid nanofiber absorbing honeycomb material, which is prepared by one-step forming using an absorbent having a nanoscale structure, excellent mechanical properties and electrical properties and para-aramid nanofibers with excellent mechanical properties. The aramid nanofiber absorbing honeycomb material has excellent mechanical properties and good absorbing properties.

[0021] The present invention uses para-aramid nanofibers as the "building blocks" of the honeycomb, which can greatly enhance the mechanical properties of the honeycomb. In addition, the surface of ANFs has abundant active groups, which can be combined with nano-scale absorbers through hydrogen bonds, avoiding the problem of easy peeling of the surface coating of traditional absorbing honeycomb materials, and having good mechanical properties and chemical stability, which can meet the application requirements of aerospace and other fields.

[0022] The present invention provides a method for preparing an aramid nanofiber absorbing honeycomb material. The preparation of traditional absorbing honeycomb materials is generally divided into two steps. The first step is to prepare the honeycomb, which includes raw material preparation, gluing, hot pressing, trimming, stretching, shaping, dipping, drying, curing and slicing, and the process is complicated. The second step is to coat a layer of absorbing coating on the surface of the honeycomb. However, the absorbing coating has the disadvantages of increased weight, low bonding strength with the shell, and easy peeling due to the organic resin contained in it. The present invention does not need to go through the above steps, and adopts a top-down strategy. First, the aramid fiber is nano-sized, and then blended with the absorbent. Only one step is required to prepare the absorbing honeycomb material, which greatly simplifies the preparation process and has excellent mechanical properties and absorbing properties. In addition, the present invention does not require additional equipment and can be carried out anytime and anywhere. It is convenient and fast, saving time and effort, and can be widely used in stealth aircraft, stealth ships, communication base stations, electrical equipment and other fields.

[0023] The present invention performs high-pressure homogenization treatment on the absorbent aqueous dispersion and the para-aramid nanofiber aqueous dispersion, thereby achieving good dispersion and blending of the absorbent and the para-aramid nanofiber. Compared with traditional mechanical stirring, the absorbent and the para-aramid nanofiber are subjected to strong shearing, impact and cavitation under high pressure to form a uniformly mixed emulsion system with good stability, avoiding the problems of uneven dispersion in the traditional stirring process and easy flocculation of materials after stopping stirring, and further improving the mechanical and absorbing properties of the absorbing honeycomb material.

[0024] The controllable vacuum-assisted filtration provided by the present invention controls the solid content of the ANFs@absorber hydrogel, thereby preparing absorbing honeycomb materials with different densities. When the solid content of the ANFs@absorber hydrogel is low, the water content is high, the water evaporates faster during the drying process, the water loss is high, and the shrinkage rate is large; on the contrary, when the solid content of the ANFs@absorber hydrogel is high, the water content is low, the water evaporates slower during the drying process, the water loss is low, and the shrinkage rate is small, thereby realizing the preparation of absorbing honeycomb materials with different densities.

[0025] The wave-absorbing honeycomb material prepared by the present invention can be adjusted automatically as needed. By controlling the insertion distance of the regular hexagonal mold and selecting regular hexagonal molds with different side lengths, wave-absorbing honeycomb materials with different densities and cell side lengths can be prepared, thereby broadening the application field and enhancing the practicality, thereby meeting its application needs in the fields of aerospace and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of the preparation process of the present invention;

[0027] Figure 2 This is a physical picture of the aramid nanofiber absorbing honeycomb material obtained in Example 1 of the present invention. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in further detail below:

[0029] A kind of aramid nanofiber absorbing honeycomb material, the raw materials for preparation include para-aramid nanofiber and absorbing agent, the mass ratio of para-aramid nanofiber to absorbing agent is (40-90): (60-10); the cell side length of the aramid nanofiber absorbing honeycomb material is 1.5-8 mm, the height of the aramid nanofiber absorbing honeycomb material is 0.5-3 cm, and the density of the aramid nanofiber absorbing honeycomb material is 50-800 kg / m 3 The absorber is a mixture of one or more of carbon nanotubes, MXene, graphene, metal and metal oxide powders and conductive carbon black.

[0030] See also Figure 1, the aramid nanofiber absorbing honeycomb material is prepared by the following method:

[0031] Step (1): using a DMSO / KOH / H2O mixed system to prepare a para-aramid nanofiber aqueous dispersion A; the para-aramid nanofiber is prepared using para-aramid short fibers; the concentration of the para-aramid nanofiber aqueous dispersion A is 1-5 mg / mL;

[0032] Step (2): stirring the absorber in deionized water and ultrasonically applying the absorber, the stirring speed is 900-1500 rpm, the ultrasonic power is 600-1200 W, and the ultrasonic time is 10-30 min to obtain an absorber aqueous dispersion B, wherein the concentration of the absorber aqueous dispersion B is 1-5 mg / mL;

[0033] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in step (1) and the absorbent aqueous dispersion B obtained in step (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the absorbent aqueous dispersion B is (40-90): (60-10)), and subjected to high-pressure homogenization to obtain an ANFs@absorbent mixed solution C, the homogenization pressure is 500-2000 bar, and the homogenization times are 15-30 times;

[0034] Step (4): filtering the mixed solution C obtained in step (3) by controlled vacuum assisted filtration until the solid content is 1.5% to 2%, thereby obtaining ANFs@ absorber hydrogel;

[0035] Step (5): insert the regular hexagonal molds into the ANFs@ absorber hydrogel obtained in step (4) at a certain distance, dry (drying temperature 30-105°C, drying time 12-48h), and take out the molds to obtain the aramid nanofiber absorbing honeycomb material. The side length of the regular hexagonal mold is 1.5-8mm, the height of the regular hexagonal mold is 1.5-4cm, and the distance between the molds is 0.5-3cm.

[0036] The present invention is described in further detail below in conjunction with embodiments:

[0037] Example 1

[0038] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 1 mg / mL;

[0039] Step (2): stirring the carbon nanotubes in deionized water and ultrasonically treating the carbon nanotubes at a stirring speed of 900 rpm, an ultrasonic power of 600 W, and an ultrasonic time of 10 min to obtain a carbon nanotube aqueous dispersion B, wherein the concentration of the carbon nanotube aqueous dispersion B is 1 mg / mL;

[0040] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the carbon nanotube aqueous dispersion B obtained in (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the carbon nanotube aqueous dispersion B is 40:60), and the ANFs@carbon nanotube mixed solution C is obtained by homogenization, the homogenization pressure is 500 bar, and the homogenization times are 15 times;

[0041] Step (4): The mixed solution C obtained in (3) is filtered by controlled vacuum assisted filtration until the solid content is 1.5%, thereby obtaining ANFs@carbon nanotube hydrogel;

[0042] Step (5): insert a regular hexagonal mold with a side length of 1.5 mm and a height of 1.5 cm into the ANFs@ carbon nanotube hydrogel at a spacing of 0.5 cm, dry at 30°C for 12 h, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material. The aramid nanofiber absorbing honeycomb material prepared according to Example 1 has a cell side length of 1.5 mm, a height of 0.5 cm, and a density of 50 kg / m 3 .

[0043] Example 2

[0044] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 5 mg / mL;

[0045] Step (2): stirring the graphene in deionized water with ultrasound, the stirring speed is 1500 rpm, the ultrasound power is 1200 W, and the ultrasound time is 30 min to obtain a graphene aqueous dispersion B, the concentration of the graphene aqueous dispersion B is 5 mg / mL;

[0046] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the graphene aqueous dispersion B obtained in (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the graphene aqueous dispersion B is 90:10), and the ANFs@graphene mixed solution C is obtained by homogenization, the homogenization pressure is 2000 bar, and the homogenization times are 30 times;

[0047] Step (4): filtering the mixed solution C obtained in (3) by controlled vacuum assisted filtration until the solid content is 2%, thereby obtaining ANFs@graphene hydrogel;

[0048] Step (5): insert a regular hexagonal mold with a side length of 8 mm and a height of 4 cm into the ANFs@graphene hydrogel at an interval of 3 cm, dry at 105°C for 48 hours, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material. The aramid nanofiber absorbing honeycomb material prepared according to Example 2 has a cell side length of 8 mm, a height of 3 cm, and a density of 800 kg / m3 .

[0049] Example 3

[0050] Step (1): preparing a para-aramid nanofiber aqueous dispersion A using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 2.5 mg / mL;

[0051] Step (2): stirring MXene in deionized water with ultrasound, the stirring speed is 1200 rpm, the ultrasonic power is 900 W, and the ultrasonic time is 20 min to obtain MXene aqueous dispersion B, the concentration of MXene aqueous dispersion B is 2.5 mg / mL;

[0052] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the MXene aqueous dispersion B obtained in (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the MXene aqueous dispersion B is 70:30), and the ANFs@MXene mixed solution C is obtained by homogenization. The homogenization pressure is 1200 bar and the homogenization times are 20 times.

[0053] Step (4): The mixed solution C obtained in (3) is filtered by controlled vacuum assisted filtration until the solid content is 1.8%, thereby obtaining ANFs@MXene hydrogel;

[0054] Step (5): insert a regular hexagonal mold with a side length of 4 mm and a height of 2.5 cm into the ANFs@MXene hydrogel at an interval of 1.5 cm, dry at 80°C for 24 h, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material. The aramid nanofiber absorbing honeycomb material prepared according to Example 2 has a cell side length of 4 mm, a height of 2 cm, and a density of 400 kg / m 3 .

[0055] Example 4

[0056] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 1 mg / mL;

[0057] Step (2): stirring the conductive carbon black in deionized water and ultrasonically treating the conductive carbon black at a stirring rate of 900 rpm, an ultrasonic power of 600 W, and an ultrasonic time of 30 min to obtain a conductive carbon black aqueous dispersion B, wherein the concentration of the conductive carbon black aqueous dispersion B is 1 mg / mL;

[0058] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the conductive carbon black aqueous dispersion B obtained in (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the conductive carbon black aqueous dispersion B is 50:50), and the ANFs@conductive carbon black mixed solution C is obtained by homogenization, the homogenization pressure is 1000 bar, and the homogenization times are 20 times;

[0059] Step (4): filtering the mixed solution C obtained in (3) by controlled vacuum assisted filtration until the solid content is 1.5%, thereby obtaining ANFs@conductive carbon black hydrogel;

[0060] Step (5): insert a regular hexagonal mold with a side length of 4 mm and a height of 2.5 cm into the ANFs@conductive carbon black hydrogel at an interval of 1 cm, dry it at 80°C for 24 h, and take out the mold to obtain an aramid nanofiber absorbing honeycomb material.

[0061] Example 5

[0062] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 1 mg / mL;

[0063] Step (2): stirring the ferroferric oxide powder in deionized water and ultrasonically treating the powder at a stirring rate of 900 rpm, an ultrasonic power of 600 W, and an ultrasonic time of 10 min to obtain a ferroferric oxide aqueous dispersion B, wherein the concentration of the ferroferric oxide aqueous dispersion B is 1 mg / mL;

[0064] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the ferroferric oxide aqueous dispersion B obtained in (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the ferroferric oxide aqueous dispersion B is 60:40), and the ANFs@ferroferric oxide mixed solution C is obtained by homogenization, the homogenization pressure is 1000 bar, and the homogenization times are 20 times;

[0065] Step (4): filtering the mixed solution C obtained in (3) by controlled vacuum assisted filtration until the solid content is 2%, thereby obtaining ANFs@ferroferric oxide hydrogel;

[0066] Step (5): insert a regular hexagonal mold with a side length of 4 mm and a height of 2.5 cm into the ANFs@ferroferric oxide hydrogel at an interval of 1 cm, dry it at 80°C for 24 h, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material.

[0067] Example 6

[0068] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 1 mg / mL;

[0069] Step (2): stirring carbon nanotubes and MXene (carbon nanotube: MXene mass ratio is 50:50) in deionized water, with a stirring rate of 900 rpm, an ultrasonic power of 600 W, and an ultrasonic time of 10 min to obtain a carbon nanotube / MXene mixed solution B dispersed in deionized water, wherein the concentration of the carbon nanotube / MXene mixed solution B is 1 mg / mL;

[0070] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the carbon nanotube / MXene mixed solution B obtained in (2) are mixed in proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the carbon nanotube / MXene mixed solution B is 80:20), and the ANFs@carbon nanotube / MXene mixed solution C is obtained by homogenization. The homogenization pressure is 1000 bar and the number of homogenizations is 20 times.

[0071] Step (4): The mixed solution C obtained in (3) is filtered by controlled vacuum assisted filtration until the solid content is 2%, thereby obtaining ANFs@carbon nanotube / MXene hydrogel;

[0072] Step (5): insert a regular hexagonal mold with a side length of 4 mm and a height of 2.5 cm into the ANFs@carbon nanotube / MXene hydrogel at an interval of 1 cm, dry it at 80°C for 24 h, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material.

[0073] Example 7

[0074] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 1 mg / mL;

[0075] Step (2): stirring carbon nanotubes and graphene (the mass ratio of carbon nanotubes to graphene is 50:50) in deionized water by ultrasonication, the stirring rate is 900 rpm, the ultrasonic power is 600 W, and the ultrasonic time is 10 min to obtain a carbon nanotube / graphene mixed solution B dispersed in deionized water, and the concentration of the carbon nanotube / graphene mixed solution B is 1 mg / mL;

[0076] Step (3): the para-aramid nanofiber aqueous dispersion A obtained in (1) and the carbon nanotube / graphene mixed solution B obtained in (2) are mixed in a proportion (the mass ratio of the para-aramid nanofiber aqueous dispersion A to the carbon nanotube / graphene mixed solution B is 90:10), and the ANFs@carbon nanotube / graphene mixed solution C is obtained by stirring and dispersing, the homogenization pressure is 1000 bar, and the homogenization times are 20 times;

[0077] Step (4): filtering the mixed solution C obtained in (3) by controlled vacuum assisted filtration until the solid content is 2%, thereby obtaining ANFs@carbon nanotube / graphene hydrogel;

[0078] Step (5): insert a regular hexagonal mold with a side length of 4 mm and a height of 2.5 cm into the ANFs@carbon nanotube / graphene hydrogel at an interval of 1 cm, dry it at 80°C for 24 h, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material.

[0079] Example 8

[0080] Step (1): preparing a para-aramid nanofiber aqueous dispersion A by using a DMSO / KOH / H2O mixed system, wherein the concentration of the para-aramid nanofiber aqueous dispersion A is 1 mg / mL;

[0081] Step (2): stirring MXene / graphene (MXene: graphene mass ratio is 50:50) in deionized water with ultrasound, the stirring rate is 900 rpm, the ultrasound power is 600 W, and the ultrasound time is 10 min to obtain a MXene / graphene mixed solution B dispersed in deionized water, and the concentration of the MXene / graphene mixed solution B is 1 mg / mL;

[0082] Step (3): the para-aramid nanofiber dispersion A obtained in (1) and the MXene / graphene mixed solution B obtained in (2) are mixed in proportion (the mass ratio of the para-aramid nanofiber dispersion A:MXene / graphene mixed solution B is 90:10), and the ANFs@MXene / graphene mixed solution C is obtained by homogenization, the homogenization pressure is 1000 bar, and the homogenization times are 20 times;

[0083] Step (4): The mixed solution C obtained in (3) is filtered by controlled vacuum assisted filtration until the solid content is 2%, thereby obtaining ANFs@MXene / graphene hydrogel;

[0084] Step (5): insert a regular hexagonal mold with a side length of 4 mm and a height of 2.5 cm into the ANFs@MXene / graphene hydrogel at an interval of 1 cm, dry it at 80°C for 24 h, and remove the mold to obtain an aramid nanofiber absorbing honeycomb material.

Claims

1. A method for preparing an aramid nanofiber microwave-absorbing honeycomb material, It is characterized in that The method comprises the following steps: preparing a para-aramid nanofiber aqueous dispersion by using a DMSO / KOH / H2O mixed system; mixing an absorber with deionized water to obtain an absorber aqueous dispersion; homogenizing the para-aramid nanofiber aqueous dispersion and the absorber aqueous dispersion to obtain an ANFs@absorber mixed solution; performing controllable vacuum-assisted filtration on the ANFs@absorber mixed solution to obtain an ANFs@absorber hydrogel; inserting a mold into the ANFs@absorber hydrogel at intervals, drying, and removing the mold to obtain an aramid nanofiber absorbing honeycomb material; The solid content of the ANFs@ absorber hydrogel is 1.5%-2%; the homogenization is performed according to the mass ratio of the para-aramid nanofiber aqueous dispersion to the absorber aqueous dispersion of (40-90): (60-10), the homogenization pressure is 500-2000 bar, and the number of homogenization is 15-30 times; the mold is a regular hexagon, the side length of the mold is 1.5-8 mm, the height of the mold is 1.5-4 cm, and the distance between the molds is 0.5-3 cm; In terms of weight, the raw materials for preparing the aramid nanofiber absorbing honeycomb material include 40 to 90 parts of para-aramid nanofibers and 60 to 10 parts of absorbers, and the absorbers are MXene.

2. The method for preparing an aramid nanofiber microwave absorbing honeycomb material according to claim 1, It is characterized in that The cell side length of the aramid nanofiber absorbing honeycomb material is 1.5-8 mm, the height of the aramid nanofiber absorbing honeycomb material is 0.5-3 cm, and the density of the aramid nanofiber absorbing honeycomb material is 50-800 kg / m 3 .

3. The method for preparing an aramid nanofiber microwave absorbing honeycomb material according to claim 1, It is characterized in that The concentration of the para-aramid nanofiber aqueous dispersion is 1-5 mg / mL; the concentration of the absorber aqueous dispersion is 1-5 mg / mL.

4. The method for preparing an aramid nanofiber microwave absorbing honeycomb material according to claim 1, It is characterized in that The absorbent and deionized water are mixed by stirring ultrasound, the stirring speed is 900-1500 rpm, the ultrasound power is 600-1200 W, and the ultrasound time is 10-30 min.

5. The method for preparing an aramid nanofiber microwave absorbing honeycomb material according to claim 1, It is characterized in that The drying temperature is 30-105° C., and the drying time is 12-48 h.

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